Molecular analysis of intestinal stem cell associated genes in colorectal cancer (CRC)

一项综合的分子分析工作比较了同一患者的原发性结直肠肿瘤和肝转移，并揭示了在转移过程中差异调节的基因和途径。另一组重要的候选基因来源于CD 133阳性结直肠肿瘤细胞中激活的基因的鉴定，这些基因被认为代表了富含癌症干细胞的细胞部分。本项目的目的是对这两组候选基因进行功能鉴定，以阐明它们在结直肠癌发生和转移过程中的作用。将在正常和结肠直肠细胞系中调节候选基因表达，并通过应用检测细胞粘附、细胞迁移和侵袭的试验来研究表型效应。基因调控后的表达和DNA甲基化谱分析将允许生成由我们的候选基因启动的转移相关过程中所涉及的分子途径和网络的系统视图。根据癌症干细胞是转移的创始细胞的概念，将使用球状体培养物深入分析来自两个顶级途径的顶级基因和成员的影响。将与子项目3和其他子项目密切合作，使用该体外系统和异种移植模型开展工作。此外，我们将使用生物活性真菌提取物和/或小分子筛选设施（EMBL和DKFZ之间建立）筛选新型抑制剂。在该子项目过程中开发的具有转移相关表型的细胞系统中检测这些抑制剂，将允许验证新出现的分子干扰策略。

An integrated molecular profiling effort compared primary colorectal tumors with liver metastases from the same patient and revealed genes and pathways that are differentially regulated in the process of metastasis. Another set of important candidate genes was derived from the identification of genes activated in CD133-positive colorectal tumor cells, which are considered to represent a cellular fraction enriched in cancer stem cells. The aim of this project is to functionally characterize these two sets of candidate genes in order to elucidate their role in colorectal carcinogenesis and the process of metastasis. Candidate gene expression will be modulated in normal and colorectal cell lines and phenotypic effects will be investigated by applying assays which test cell adhesion, cell migration and Invasion. Expression and DNA methylation profiling upon gene modulation will allow the generation of a systematic view of the molecular pathways and networks involved in metastasis-related processes initiated by our candidate genes. Following the concept of cancer stem cells äs the founding cells of metastases, the effect of top-ranked genes and members from the two top-ranked pathways will be analyzed in depth using spheroid cultures. Work using this prime in vitro System and xenotransplant models will be performed in close collaboration with subproject 3 and other subprojects. Furthermore, we will screen for novel inhibitors using biologically active fungi extracts and/or the small molecular screening facility (established between the EMBL and the DKFZ). The testing of these inhibitors in the cellular Systems with metastasis-related phenotype, which are developed in the course of this subproject, will allow validation of newly emerging molecular interference strategies.